Saint-Raphaël: Clay Soil, Subsidence and Cracks – Official Data

The complete chronology of the 21 natural disasters recognised in Saint-Raphaël

Each line = an event recognised by an interministerial decree published in the Journal officiel (GASPAR database):

• 🔵 08/1983 → 08/1983 – Floods (prefectoral decree of 15/11/1983)
• 🔵 10/1987 → 10/1987 – Floods (prefectoral decree of 02/12/1987)
• 🔵 12/1990 – Floods (prefectoral decree of 14/05/1991)
• 🔵 09/1992 → 09/1992 – Floods (prefectoral decree of 23/06/1993)
• 🔵 04/1993 → 04/1993 – Floods (prefectoral decree of 08/03/1994)
• 🔵 10/1993 → 10/1993 – Floods (prefectoral decree of 14/12/1993)
• 🔵 09/2002 – Floods (prefectoral decree of 29/10/2002)
• 🔵 08/2005 → 08/2005 – Floods (prefectoral decree of 02/03/2006)
• 🔵 12/2006 → 12/2006 – Floods (prefectoral decree of 24/04/2007)
• 🔵 12/2008 → 12/2008 – Floods (prefectoral decree of 16/10/2009)
• 🔵 11/2011 → 11/2011 – Floods (prefectoral decree of 18/11/2011)
• 🔵 10/2012 – Floods (prefectoral decree of 10/01/2013)
• 🔵 10/2015 – Floods (prefectoral decree of 07/10/2015)
• 🔴 07/2016 → 12/2016 – Drought – clay shrink-swell (RGA) (prefectoral decree of 09/03/2018)
• 🔵 11/2019 → 11/2019 – Floods (prefectoral decree of 28/11/2019)
• 🔵 12/2019 → 12/2019 – Floods (prefectoral decree of 12/12/2019)
• 🔴 04/2020 → 06/2020 – Drought – clay shrink-swell (RGA) (prefectoral decree of 18/05/2021)
• 🔴 04/2022 → 09/2022 – Drought – clay shrink-swell (RGA) (prefectoral decree of 03/04/2023)
• 🔴 04/2023 → 09/2023 – Drought – clay shrink-swell (RGA) (prefectoral decree of 18/06/2024)
• 🔵 09/2024 → 09/2024 – Floods (prefectoral decree of 13/10/2024)
• 🔵 10/2024 – Floods (prefectoral decree of 15/12/2024)

Expert reading: 4 droughts and 17 floods. Clusters (several decrees close together) flag up crisis periods – the summer of 2022-2023 is the best recent example. An owner whose damage dates from a covered period has a solid Cat Nat file; outside a covered period, the way forward is an action against the seller.

The official clay classification (GéoRisques/BRGM)

The GéoRisques platform (BRGM) classifies Saint-Raphaël at medium exposure to clay shrink-swell (RGA). This is the benchmark level used by insurers and notaires to assess the risk on a plot. Worth noting: radon potential class 3 across the commune (IRSN/GéoRisques data) – a health-and-building watch point in the affected zone.

This classification completes the decree history above: the hazard rating says what can happen, the decrees say what has already happened. A house rated “medium exposure” that has come through one or more dry summers carries a risk of damage that is all the better documented.

What the official clay mapping says

The GéoRisques platform (BRGM) classifies Saint-Raphaël at medium exposure to clay shrink-swell (RGA). This is the benchmark level used by insurers and notaires to assess the risk on a plot. Worth noting: radon potential class 3 across the commune (IRSN/GéoRisques data) – a health-and-building watch point in the affected zone.

This classification completes the decree history above: the hazard rating says what can happen, the decrees say what has already happened. A house rated “medium exposure” that has come through one or more dry summers carries a risk of damage that is all the better documented.

What 35 years of local rainfall tell us

The area’s weather archives cover 35 complete years (1991-2025). The driest ever recorded: 2007, with 398 mm over the year, against a local average of 821 mm. 2022 ranks as the 5th driest year out of 35 (578 mm against an average of 821 mm); 2023 follows in 3rd place (557 mm).

This ranking gives the true measure of the recent sequence: when the years 2020-2023 sit high up the list of dry years, the clay has had no time to rehydrate between episodes – the textbook scenario for delayed cracking. The reverse is just as instructive: a very wet year following an exceptional drought triggers abrupt swelling of the ground.

Damp, water ingress and rising damp in Saint-Raphaël

Damp in a wall can have four causes – rising damp, water ingress, condensation or a leak – and the treatments are completely different depending on the origin.

You have a damp problem in Saint-Raphaël and you may already have read that it needs resin injections or a mechanical ventilation system. My message: not so fast. Without a precise diagnosis of the origin of the problem, these treatments can be useless, or even make things worse.

The 4 causes and how to recognise them

• Rising damp: stains at the base of the walls, over a height of 50 to 100 cm, often with crumbling render and efflorescent salts. Common in the older houses of central Saint-Raphaël with no damp-proof course.
• Water ingress: localised marks, often high up or near a roof, a window or a terrace. Worsens after rain, typical of buildings exposed to Mediterranean downpours.
• Condensation: appears on surfaces, often in poorly ventilated rooms, bathrooms, kitchens, with black mould in cold corners.
• Leak: a localised stain near a pipe, a bathroom or a kitchen, sometimes accompanied by unexplained excess water consumption.

The trap of the diagnosis sold by the treatment contractor

Many firms that carry out the diagnosis are also the ones selling and installing the treatment. The risk is obvious: a diagnosis steered towards the most profitable solution for them – injections or tanking – even when the real cause is simple water ingress or a ventilation defect. An independent expert, with no commercial interest in the works, identifies the true origin before any recommendation.

For an independent diagnosis in Saint-Raphaël, contact us. To go further on this subject, read the damp guide for 06, 83 and 13.

What characterises Saint-Raphaël in building surveys

In Saint-Raphaël, the diversity of the ground encountered on site largely explains the frequency of the damage we record: between the hills of the Esterel and Valescure, the flatter neighbourhoods towards Boulouris or the Argens valley at the entrance to the town, clay soils sit alongside pockets of rock and fill, creating very uneven responses from one plot to the next to the drought-rehydration cycles. The built fabric is particularly exposed: the Provençal villas and the houses of the large estates built in the 70s-80s, a period of intense urbanisation in the area, very often rest on shallow foundations that were not designed for the swelling clay we know how to identify today. Add to that the vegetation typical of the area – maritime pines and cork oaks planted near the houses for shade – whose roots draw water from depth and intensify the shrinkage of the ground in summer, causing differential settlement that translates into façade cracks or cracking at the corners of openings. Renovations and extensions carried out over the last twenty years on this older stock, often without underpinning, weaken further structures already stressed by this ground movement. It is this combination of slope, heterogeneous soil and period foundations that makes, in our eyes as experts working regularly in the area, clay-related cracks so characteristic of Saint-Raphaël.

Saint-Raphaël: drought, clay and cracks – what the official database says, and what to do with it

If your house in Saint-Raphaël is cracking, the first question to settle is: does the damage fall within a recognised natural disaster period? GASPAR records 4 drought prefectoral decrees (full list below) and 17 flood decrees, i.e. 21 natural disaster declarations (Cat Nat) for the commune. Local rainfall confirms the mechanism: 4 years below average in a row (2020 to 2023), then a rebound to 1,153 mm in 2024 – exactly the scenario that puts foundations under strain along the corniche d’Estérel. In practical terms: note the date your cracks appeared, it determines everything that follows.

Cassini Expertise, an independent building expert, handles cracks and drought-related damage in Saint-Raphaël and throughout the Var. This page brings together the commune’s official data, with no commercial slant – use it to work out whether you should be worried, declare a claim, or consult a solicitor.

Is my house covered by a drought decree in Saint-Raphaël?

The GASPAR database (decrees published in the Journal officiel since 1982) counts 21 natural disaster declarations (Cat Nat) for the commune:

• 4 drought prefectoral decrees (differential ground movement linked to clay shrink-swell (RGA))
  • event of 01/07/2016 (prefectoral decree of 09/03/2018)
  • event of 01/04/2020 (prefectoral decree of 18/05/2021)
  • event of 01/04/2022 (prefectoral decree of 03/04/2023)
  • event of 01/04/2023 (prefectoral decree of 18/06/2024)
• 17 flood prefectoral decrees and storm

What to do with it: compare the date your cracks appeared with these four periods. If it matches, head to your insurer with a claim declaration – you have 30 days after publication of the decree to file it. If your cracks fall outside these periods, the Cat Nat route is closed; what remains is the claim against the seller for hidden defect (vice caché) or fraud (dol), covered further down.

Am I in an at-risk clay zone? The official classification

The GéoRisques platform (BRGM) classifies Saint-Raphaël at medium exposure to clay shrink-swell (RGA). This is the level your insurer and your notaire already consult to assess your plot – you can do the same by entering your address on georisques.gouv.fr before any purchase. Another point to check on the same platform: the commune is at radon potential class 3 (IRSN/GéoRisques data), a ventilation issue to watch if you spend time in a basement or on the ground floor.

This classification completes the decree history above: the hazard rating says what can happen, the decrees say what has already happened. A house rated “medium exposure” that has come through one or more dry summers deserves a foundation check, even with no visible crack today.

Why is my house cracking now? Local rainfall

Annual rainfall recorded on the Saint-Raphaël weather grid (Open-Meteo data):

• 2019: 1,121 mm · 2020: 628 mm · 2021: 609 mm · 2022: 578 mm · 2023: 557 mm · 2024: 1,153 mm
• Average over the period: 774 mm/year, driest year: 2023 (557 mm)
• Four consecutive years below average: 628 mm in 2020, 609 mm in 2021, 578 mm in 2022, 557 mm in 2023
• Then 2024 climbs back to 1,153 mm, i.e. +49%

Shrink-swell plays out in two stages: the drought dries out the clay at depth (shrinkage, first cracks), then the return of the rain rehydrates the ground at a stroke (swelling, differential movement). If your house sits on shallow foundations – the case for the majority of villas built between 1970 and 2000 – expect cracks to appear 12 to 24 months after a dry spell, not during it. That is why a crack appearing “for no reason” in 2025-2026 may well date from the 2022-2023 drought.

This week’s drought watch (as at 04/10/2026)

In the commune: recent rain (3 days ago). Rainfall over the last 30 days: 8 mm, against roughly 57 mm expected at this time of year – an 86% deficit.

A sustained deficit over this window, especially in the growing season, often precedes by a few weeks the drop in the water table shown above: it is the first signal owners can track themselves, before any cracks appear.

This week’s drought watch (as at 05/10/2026)

In the commune: recent rain (4 days ago). Rainfall over the last 30 days: 8 mm, against roughly 59 mm expected at this time of year – an 86% deficit.

A sustained deficit over this window, especially in the growing season, often precedes by a few weeks the drop in the water table shown above: it is the first signal owners can track themselves, before any cracks appear.

This week’s drought watch (as at 12/10/2026)

In the commune: recent rain (4 days ago). Rainfall over the last 30 days: 85 mm, against roughly 69 mm expected at this time of year – a 23% surplus.

A sustained deficit over this window, especially in the growing season, often precedes by a few weeks the drop in the water table shown above: it is the first signal owners can track themselves, before any cracks appear.

This week’s drought watch (as at 19/10/2026)

In the commune: recent rain (2 days ago). Rainfall over the last 30 days: 94 mm, against roughly 80 mm expected at this time of year – an 18% surplus.

A sustained deficit over this window, especially in the growing season, often precedes by a few weeks the drop in the water table shown above: it is the first signal owners can track themselves, before any cracks appear.

Aquifer memory: 24 years of measurements, a well-documented context

The reference piezometric station for the area (002HERB) has been monitoring the aquifer since 1967 – 24 years of records. As at 31/12/2004, the average level over the last thirty days is 11.03 m NGF (French ordnance datum). Across the whole record, the aquifer has spent 41.7% of its time below this level: a level close to the station’s average.

• Last equivalent episode: 25/12/2004 – 21.8 years ago
• Frequency: 57 similar episodes recorded since 1967, i.e. an annual return on average – in hydrologists’ language, an intermediate episode
• Historic minimum: 9.89 m NGF, reached on 17/03/1968

This long memory changes how the risk is read: a low level is not just a weather episode, it is an event whose frequency is known. For a house on clay, it is this frequency that tells you the probability of fresh settlement – and therefore how urgent the precautions are.

Are my cracks serious? The warning signs

• A stair-step crack, passing through the wall, open by more than 2 mm – get a ruler out, this is the threshold that justifies a call
• A crack that evolves: fit a plaster tell-tale or a dated crack gauge, recheck 2-3 months apart
• Associated damage: doors and windows sticking, tiles splitting diagonally, render blistering
• Clay ground, a tree close to the façade, a failed gutter or drainage

With 4 drought prefectoral decrees on the commune’s tally, a build-up of several of these signs justifies a survey before any repair – and before any buying or selling decision. Do not fill an active crack before having it surveyed: you lose the proof of how it developed.

Buying or selling a cracked house in Saint-Raphaël: what recourse?

Between the recent drought decrees and the volume of transactions, quite a few properties are changing hands with damage kept quiet. If you discover cracks after the purchase, two levers exist:

• Hidden defect (article 1641 of the Code civil): serious cracks, not detectable at the viewing, predating the sale → price reduction or cancellation of the sale. You have 2 years from discovery to act – do not drag your feet, have the damage dated by an expert quickly
• Fraud (dol) (article 1137): the seller knew and concealed the damage → cancellation and damages, 5-year deadline; the commune’s GASPAR decree then underpins the file if the dates match

To launch either procedure, get support from a property-law solicitor (avocat) – the technical survey dates and qualifies the damage, the solicitor handles what follows.

What does an expert do in cases of drought-related cracks in Saint-Raphaël?

• On-site visit: crack survey and classification, crack-width measurements, functional damage (doors, windows, tiling)
• Context analysis: clay nature of the ground, the commune’s natural disaster declaration (Cat Nat) history (4 drought decrees), local dry spells
• Costing of works: underpinning, injections, drains – several scenarios depending on severity
• A written report your insurer or solicitor can use to support a claim or legal proceedings

For an on-site survey: building expert in Saint-Raphaël.

Independent expert, with no ties to any building contractor. Request a visit in Saint-Raphaël – see also our complete RGA and Cat Nat guide for 06, 83 and 13.

Soil surveys on clay ground: what the regulations say

The requirement for a prior geotechnical survey has applied since 1 October 2020 (ELAN law, art. 68); the new exposure map of 1 July 2026 widens its scope. This obligation, stemming from ELAN law no. 2018-1021, article 68 (decree no. 2019-495 of 22 May 2019), applies to Saint-Raphaël (medium exposure in the BRGM classification).

• What it changes for building: the soil survey is no longer an option – the ELAN law makes it compulsory in an exposed zone for every sale of building land and every construction contract. Adapted foundations, ground treatment, drainage arrangements: the specifications flow directly from the survey.
• What it changes when buying a recent property: ask whether the survey was carried out and which specifications were applied. A house built without following the geotechnical recommendations on clay soil is a medium-term cracking risk.
• What it changes when selling: the absence of a survey on a property built before the obligation is not a defect in itself – but if damage appears, a seller who knew about it and concealed it exposes themselves to an action for fraud (dol).
• The link with the data above: Saint-Raphaël combines medium exposure with a well-documented history of drought decrees. Building or buying here without checking the nature of the ground means building on a known and measured risk.

Cassini Expertise handles these files: compliance checks between geotechnical specifications and execution, damage surveys on clay ground, second-opinion expert assessments. Request a consultation.

Frequently asked questions

Is Saint-Raphaël in an at-risk clay zone?

The Var is very broadly covered by the clay shrink-swell (RGA) hazard (BRGM mapping, viewable on georisques.gouv.fr). In Saint-Raphaël, the 4 drought decrees recognised by GASPAR confirm the risk is anything but theoretical. If you are buying, check the classification of the exact plot before signing.

Is my cracked house in Saint-Raphaël eligible for compensation?

Only if the damage can be tied to a period covered by a decree (the latest recognised periods: 2018, 2021, 2023, 2024) and if the declaration was made within 30 days of publication. Failing that, the action against the seller remains – and there, dating the damage through a survey becomes decisive in choosing between hidden defect and fraud (dol).

Can this data be verified?

Yes: the decrees come from the GASPAR database (Journal officiel, open data sets, 2025 update), the rainfall from Open-Meteo weather archives for the Saint-Raphaël grid. Cassini Expertise merely compiles them, without adjusting anything – you can cross-check them yourself on georisques.gouv.fr.

Find out more: Article 1641 of the Civil Code and the hidden defects warranty (garantie des vices cachés), explained.

Survey carried out by Frédéric Faucouneau, independent building expert – Antibes, Alpes-Maritimes (06), Var (83), Bouches-du-Rhône (13). Find out more

📅 Last updated 06/11/2026 - Cassini Expertise, independent building expert – departments 06, 83 and 13.